Solubility curves of four ionic salts $X$,$Y$,$Z$,and $W$ are given below. In which case is the value of $\Delta H_{sol.} < 0$?

What is dissolution?

At $298 \ K$,Henry's law constant for $CO_2$ in water is $1.67 \times 10^8 \ Pa$. At $298 \ K$,the quantity of $CO_2$ in $1000 \ mL$ of soda water when packed at $1.67 \times 10^2 \ kPa$ $CO_2$ pressure in $mol \ L^{-1}$ is: (water density $= 1.0 \ g \ cm^{-3}$)

Which is the correct order for the solubility of the following compounds in $n$-octane (at identical conditions)? $I$) Cyclohexane $II$) $KCl$ $III$) $CH_3OH$ $IV$) $CH_3CN$

The values of the Henry's law constant of $Ar$,$CO_{2}$,$CH_{4}$ and $O_{2}$ in water at $25^{\circ} C$ are $40.30$,$1.67$,$0.41$ and $34.86 \ kbar$,respectively. The order of their solubility in water at the same temperature and pressure is

The Henry's law constant for the dissolution of a gas in an aqueous medium is $3 \times 10^2 \ atm$. At what partial pressure of the gas will the molality of the gas in the aqueous solution be $\frac{5}{9} \ m$?